Die and tap holder.



a 9 m 37 c 0 d e t n e t a BI J NICKLIN, JR

nu: AND TAP HOLDER.

(Application filed Kay 26, 1899.)

(No Model.)

INVENTDIT'. JOHN NlCKLlN JR.

Ill/Il/ll/l/I/l/A UNITE TA'IES JOIIN NICKLIN, JR, OF CLEVELAND, OIIIO.

DIE AND TAP HOLDER.

SPECIFICATION forming part of Letters Patent No. 634,269, dated October 3, 1899.

Application filed May 26, 1899. Serial No. 718,320. (No model.)

To all whom it may concern.- v

Be it known that I, JOHN NIOKLIN, J12, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Die and Tap'Holders; and I do declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to die and tap holders; and among the objects of the invention is the overcoming of all side strain on the thread when the die is backing off, thereby obtaining a thread that is more accurate to pitch and avoids the stripping, crossing, or mutilating of the thread when the die is backing ofl.

Another object of the invention is to provide a die and tap holder that will out either right orleft hand threads by a mere exchange of dies or taps therein for right or left hand work. v I Y A further object is to produce a stronger or more powerful die or tap holder than heretofore within a given compass and to generally improve the operation, as well as to simplify and improve the mechanism, all substantially as shown and described, and particularly pointed out in the claims.

In the accompanying drawings, Figure 1 is a longitudinal sectional elevation of my improved die and tap holder, and Fig. 2 is a plain elevation thereof. Fig. 3 is a cross-section on line 2 2, Figs. 1 and 2; and Fig. 4 is a perspective view of the head of the reversingbolt, shown as lifted or raised in its sleeve to change position, as hereinafter fully described.

A represents the casing proper, which may be of any preferred or suitable construction, but is shown in this instance as having a head portion a and a tubular stem at, open at both ends. About the head is a band-like enlargement a in which is inserted a tubular plug 2, adapted to receive and support the plunger-bolt 3, which enters the head Ct. This bolt has a reduced stem with a head 4 on its outer end, and about said stem isa spring 5, adapted to bear on the bolt 3 and keep it down in engaging position. The head of plug 2 is shown as having two opposite holes 6, and

on the head 4 is a single pin 7, designed to be set in either hole 6, according as a right or a left hand die or tap is used, this construction enabling the bolt 2 to be rotated in either direction by taking hold of head 4 and withdrawing it to change the pin 7 from one hole to the other. This is the work of a moment in any case, and when the bolt is replaced it remains there until purposely changed.

B represents the holder or stock for holding the die or tap, which is removably secured thereto, a ,die D being shown in this instance and fastened by screwid. The said holder B has certain novel features of construction not hitherto known, so far as I am aware, consisting of a tubular stem I), extendin g into and fitting closely within the tubular portion a of the casing A.

In the operation of holder B it is designed to have the same free to slide back and forth in the casing A, and the stem 1) is of such length as to accommodate itself to all such sliding movements. This bridges the space between the body portion 1) of the holder 13, which fits closely all around in the casing A and'the inner end of the body a when the holder B is more or less withdrawn, as in Fig. 1, and prevents chips or dirt of any kind accumulating in the space behind the body I), and the said stem Z) serves the further purpose of a guide and steadying means in the casing A. By having both tubes at and I) open throughout I am enabled to thread a rod without limit, which is a very important ad-.

vantage in my construction.

Another feature of novelty in holder B is the longitudinal groove or channel b one on each side, oppositely, as here shown, and adapted to be engaged by the bolt 3 in one direction only at a time, the bolt having a bevel at one side which will cause it to disengage if the die be turned oppositely to that it is intended for the time being to hold; but a mere reversal of the bolt will cause it to engage the opposite side of the channel and be free the reverse direction, and two such channels are shown, so that engagement will be effected when reversal is made before too much speed is attained. To make the change, withdraw the plunger and turn it half way around and engage its pin with the opposite hole 6, and the reversal follows. Small pins 8 at the ends of channels 12 serve as stops for the bolt 3, so that the holder 15 cannot be withdrawn for the casing during its operations.

It will be understood that this device can be used on an automatic screw-machine or on a hand screw-machine or on any other machine to which it can be adapted.

hat I claim for its operation is that it is impossible to strip or cross ormutilate the thread in any way after it is cut and the die is backing off unless the die itself is defective; also, that by having the two grooves 11 which run lengthwise 011 the outside of the body Z), and the spring-pressed bolt which acts thereon the holder can be used for cutting either right or left hand threads, a feature of material advantage in machines of this kind.

It will be noticed that when the holder 13 is turned in position so that the spring-bolt connects with one of the grooves the holder can be taken hold of and moved in or out for a considerable distance, and the object of this is that as this holder will be used on automatic machines more than anything else it affords facilities for speed of operation and handling believed to be entirely new in this art. Suppose, for example, that it is engaged in cutting sixteen threads per inch and the spindle of the machine is making sixteen turns per minute. Then the tail-stock or turret-head in which the die-holder is held, as the case may be, would have to move forward one inch per minute and also backward at the same rate to take the die off; but suppose the spindle speed and thrret movement variedthatis, the spindle made sixteen revolutions while the turret only traveled, say, seven eighths of an inch. Then the dieholder must have that end play to allow for it.

hen the die is driven forward, the pins 9, which are set in the holder, engage the pins 10 in the casing, and the spring-bolt only comes into service when the die is backing oti after the thread has been cut, and the pins are disengaged by the drawing out of the holder; but the bolt is set so it will spring into the groove as soon as the spindle is reversed and the groove is reached after the pins disengage, and it connects therewith almost instantly, as the spindle has only to reverse-a fraction of a revolution when it comes into action, thereby avoiding all momentum also one or more sets of pins 9 and 10. In the present construction there are two opposite grooves b and two sets of pins in line with the grooves b on the holder B and the said sets arranged to be engaged at the same time. This throws the bolt 3 on the land between the grooves b when the pins are in engagement and in position to drop into the first groove when the holder is rotated and withdrawn sufficiently to disengage the said pins.

What I claim is 1. The casing, the holder therein longitudinally grooved and opposite pins thereon to make working engagement and a springpressed bolt in the casing to engage in the said grooves when the direction of rotation of said parts is reversed after the pins are disengaged, substantially as described.

2. The casing and the holder slidably supported therein and having longitudinal grooves, pins in said parts to engage one another when the holder is at work and thus rolate the holder, a spring-pressed bolt in the casing to engage in either of said grooves in the holder when the direction of rotation of said parts is reversed after the said pins are disengaged, substantially as described.

3. The casing having a tubular extension on its rear open at both ends, in combination with the holder having a tubular stern eutered into said extension and agroove lengthwise on its outside, and a spring-pressed bolt supported in the casing and engaged in said groove, and means at the ends of said groove to confine the bolt, substantially as described.

4. The holder havingalongitudinal groove on its surface and'a tubular stem centrally at its rear, in combination with the casing having an extension in which said stem is supported, opposite pins on the casingand holder, and a spring-pressed bolt constructed to be set to catch in the said groove in the holder when the direction of rotation of said parts is reversed after the pins are disengaged, substantially as described.

\Vitness' my hand to the foregoing speciiication this 20th day of May, 1899.

JOHN NICKLIN, JR. 

